The present invention relates generally to an improved liquid/abrasive jet material cutting system, and more particularly to such a system which provides an improved arrangement for the introduction and/or injection of abrasive particles into the stream of high pressure liquid forming the jet. More specifically, the present invention relates to an improved delivery system for controllably, accurately, and reliably introducing abrasive to a cutting head through which water is being passed for use in creating a liquid/abrasive jet intended for material cutting operations.
High pressure water is frequently utilized in operations for forming cuts in hard or brittle material, and also for the formation of cuts involving unusual or difficult-to-machine patterns. The utilization of water jets for such operations have proved to be highly effective and desirable. In improving these systems for enhancing the utility, speed and effectiveness of the water jets for a variety of applications, abrasive particulate is injected into the fluid flow. However, it is frequently difficult to appropriately and effectively meter the flow of such particulate to the cutting heads, and the present invention provides a system for rendering the metering of such delivery more reliable and effective.
Abrasive delivery systems perform the function of storing and conveying the abrasive particles over varying distances from the storage site for the introduction to the jet. The conveying function is normally achieved through the use of a pneumatic drive. When long distances are involved for the transfer of the abrasive to the jet system, problems may be encountered at the delivery site. In order to more effectively control the flow and hence the delivery, various metering systems have been proposed and utilized. However, present metering systems have not proven to be effective and reliable over periods of time, and improvements are desirable. The present delivery system has proven effective in improving both reliability and accuracy of the delivery system. When so undertaken, the versatility and adaptability of water jet cutting systems is enhanced, and the abrasive-ladened water jet provides a means for cutting through virtually any known material.